For the fabrication of mechanical parts it is desirable to use a device for supporting the parts during the fabrication process. For example, in the aircraft industry it is necessary for many of the aircraft parts to be cleaned, coated with an anticorrosive substance, and then primed and painted. One method of accomplishing this procedure is to insert the parts first in a liquid bath containing the cleaning solution, then in another liquid bath containing a plating solution, and then into a hot water rinse bath. The part is then dried before applying a primer coat and paint.
In order to properly support parts of various sizes and shapes while in the baths as well as during the priming and painting processes, it is necessary that the parts be held securely but with a minimum amount of contact so that their surfaces are not masked. Furthermore, it may be desirable to subject the parts to an anodized plating process in which electrical contact must be made with the parts.
Conventionally, parts have been supported on racks having bendable tabs which are bent into position to hold the parts, and then bent back out of position so that the parts can be removed from the racks. This procedure introduced several problems including unwanted separation of the tabs from the racks due to metal fatigue. In addition, unsatisfactory masking of the parts by the racks prevented proper coating by the liquid solutions and paint. Furthermore, the racks tended to retain small amounts of the solution when removed from the baths so that when the racks were placed in a different bath, this bath solution became contaminated.
Other conventional racks have been disclosed. For example, in U.S. Pat. No. 4,615,785 by Pulido there is disclosed a clip for securing a workpiece to a bar for suspending the workpiece in a liquid bath. Furthermore, in U.S. Pat. No. 4,679,526 by Dziedzic there is disclosed a holder for a workpiece wherein the holder is made from a single piece of springy wire which is attached to a carrier for transporting the workpiece along a predetermined path.